Ore drainage and leaching tank.



PATENTBD OCT. 1s, 1904.

No.A 772,389.

J. E. WEBB. ORE DRAINAGE AND LBAGHING TANK.

APPLICATION FILED 1320.12, 1903.

Patented October 18, 1904.

UNITED STATES VPATENT OEEICE.

JEAN F. WEBB, OF DENVER, COLORADO.

ORE DRAINAGE AND LEACHING TANK SPECIFICATION forming part of Letters Patent No. 772,389, dated. October 18, 1904.

Application filed December 12, 1903. Serial No. 184,965. (No model.)

T0 a/Z L11/2,0m, it may con/cern,.-

Be it known that I, JEAN F. WEBB, a citizen of the United States, residing in the city of Denver, in the county of Denver and State of Colorado, have invented certain new and useful Improvements in Ore Drainage and Leaching Tanks, of which the following is a full, clear, and exact description, reference being had to the accompanying drawings, form- ,ing part of this specification.

My invention has for its principal objects the rapid and economical collection, drainage, and treatment of slimes in cyanid-mills, being particularly intended to obviate the necessity of using a filter-press in the final treatment of slimes pulp; but it may be used for the cyanid treatment of ore direct or for any other material or purposes for which its peculiar construction is adapted. By its use three very marked improvements over prese-nt methods are attained, Viz: first, the rapid separation and removal from the slimes of the excess of fluid contained therein; second, the thorough treatment and compression of the pulpy mass to extract the values therefrom without the expense of rehandling and without the extra cost of a filter-press equipment; third, the reduction in volume of the enormous body of excess cyanid solution now required to be carried in stock by wet crushing-mills.

My invention consists in features of novelty hereinafter fully described, and pointed out in the claims.

In the usual wet-crushing cyanid process the ore is crushed in mortars by stamps using solvent cyanid solution of suitable strength for battery purposes. As the crushed mass pours out of the mortar it is caught and conducted through spitzkasten or hydraulic classifiers, which mechanically separate the sands or coarser portions of the ore from the slimes. The sands are run into ordinary leachingtanks and are treated by the usual percolation methods. Percolation being, almost impossible with slimes, they are run into separate tanks and allowed to stand until ,the values are dissolved and the slimy particles have settled into a pulpy mass on the bottom of the tank. rI he excess of the clear cyanid solution containing the values is then decanted oif from out the solution remaining therein.

the top by means of siphons, and t-he slimy pulp on the bottom is removed and placed in filter-presses and there compressed to force Another method of slimes treatment is to agitate them for some time with the solution before settling, then decant off the surplus solution and place the pulp in filter-presses so arranged that highly-compressed air can be forced through the compressed cakes of pulp to dry them. Then wash-water is forced through the dried cakes by means of compressed air until the remaining values are washed out, when the filter-presses are opened and the leached mass thrown away. These methods may vary slightly in dierent mills; but the usual practice is as stated where any attempt is made to save the slimes values. In some mills they are thrown away as soon as Separated from the sands.

My invention will gather the slimes and enable their values to be extracted more cheaply and rapidly than it can be done by filterpresses, and, owing to the rapid drainage, all excess of cyanid solution or battery water contained in the slimes is quickly removed and made available for reuse in the battery. I accomplish these results by means of a drainage and leaching tank having double walls and bottoms with an annular space between them, the outside shell having solid sides, top, and bottom, with openings in it so arranged that it can be made air and water tight when under pressure and the inner shell having its sides and bottom perforated and covered with suitable filtering material. Inside of the double walls and preferably in the center is a much smaller secondary hollow compartment or pressure stand-pipe, which is also' perforated and covered on the outside with suitable filters to prevent it from being filled with slimes during the filling of the tank. This central pressure stand-pipe is connected at the top with hydraulic-pressure pipes supplying either solvent solution or wash-water, as required. It is also so arranged that the Huidpressure can be cut off and compressed air introduced into it and used in forcing the liquid contents in the pulp contained in the tank outwardly and downwardly through the perfo- IOO rated sides and filtering material into the annular space between the sides and bottoms.

The supply-pipes furnishing the solvent solution, wash-water, or compressed air are so arranged with proper connections that the supply and pressure of any one can be reversed from its flow into the central standpipe and directed into the annular space between the walls and bottoms, forcing the pressure inwardly through the perfor-ations and filters into the pulp, tlius cleaning the filters and counteracting any packing of the pulp against them. 1

Figure I is a perspective view of myimproved drainage and leaching tanks with parts in vertical section. Fig. II is a detail vertical section showing the manner of connecting the solution and water pipes to the tanks in order to effect a reverse flow for cleaning purposes. After separation from the sands the slimes are run directly into the drainage and leaching tank through the filling-pipe 1 and the manhole 2. The surplus cyanid solution or liquid contained in the slimes at once begins to drain out through the filtering materials 3 and 4 and the perforated inner shell 5 and is caught and held in the annular space between the inner shell 5 and the solid shell 6, whence it runs out through the drainagepipes 7 and 8 and is pumped back to the usual storage-vat, (not shown,) or, if sufiiciently rich in dissolved values, it may be first conducted through the precipitation-'boxes before reuse in the battery. The filters 3 and 4 prevent the slimes from running through with the liquid, and they gradually settle on the bottom of the tank and accumulate until the tank is filled. The supply is then cut off by closing the valve in the filling-pipe 1. The manholes 2 are then closed, the valve in the solution-pipe 9 is opened, and fresh cyanid solution is admitted into the central pressure stand-pipe 10, which is surrounded by filtering materials 3 and 4, The pressure of the column of solution forces it through every particle of the slimes pulp and out through the filtering' materials 3 and 4 and the perforations of the inner shell 5, where .it drains into the annular space between the outer solid shell 6 and the perforated inner shell 5, from whence (as stated) it is carried off through the drainage-pipes 7 and 8, passing through precipitation-boxes into a sump (not shown) and is pumped up tothe top ofthe solution-pipe again. This operation is continued until the valuesare all dissolved, when the supply of solution is cut ofi'. If during the leaching process the pressure Ifrom the central stand-pipe 10 should pack the pulp on the side lters and interfere with the drainage, the flow of the solution can be reversed -by introducing it through the pipe 12 and branch 12a into the annular space between the two walls and forcing it inwardly through the perforations and the filters 3 and 4, freeing and 65 cleansing them and draining off through the drainage-pipe 8. This cleansing may be supplemented by introducing compressed air into the annular space through the air-reversing pipe 15 and its branch 15, which will thoroughly open the pores of the filters. Should the filters on the perforated bottom 13 become clogged, the solution can be introduced between the solid and perforated bottoms through the lower'portion of the pipes 12, so that it will rise upwardly through the perforations and filters, freeing and cleansing them, and drain off through the side filters and out through the drainage-pipe 7, and this also may be supplemented by introducing compressed air underneath the perforated bottom 13 through the lower portion of the airreversing pipe 15. When the leaching is completed, compressed air is admitted into the perforated pressure stand-pipe 10 through the air-pipe 14, the effect being to at once compress the pulp, and thus force or squeeze out all of the solution held therein, and the pressure of the compressed air may be alternately reversed through the pipe 15 until the pulp is as dry as is desired, when the supply is cut off. W ash-water is then admitted into the pressure stand-pipe 10 by opening the valve in the water column 16 and is forced by its own pressure through the leached mass to wash out the remaining values, being caught in the annular space and discharged through the drainage-pipes 7 and 8. The pipe 16 has a branch 19 connected to the tanks the same as pipe 12 and which may be used to cause the reverse fiow for cleaning purposes. After being thoroughly washed the leached and worthless pulp is quickly discharged from the tank by opening the discharge-valves 17 and 18 in the bottom of the tank and turning on the pressure of the water column 16, alternating the flow of the water through the pressure stand-pipe 10 and the water-reversing pipe 19 until the tank is empty and clean.

In amalgamating-mills, Where the ore is crushed in clear battery-water, the tailings or slimes after passing over the plates and concentrators are run into my improved tank, the battery-water forced out of them by compressed air, the solution admitted through the pressure standpipe, and the leaching and washing proceeded with as above described.

In dry crushing-mills the tank is filled with the dry ore or with the dust from the sizingscreens or -bag-houses, and the valve in the s0- lution-pipe 9 is opened, when the pressure of the cyanid solution at once forces it outwardly through the perforations and filters of the pressure stand-pipe, so that it radiates evenly and Vquickly through the ore until every atom is thoroughly saturated with it, when the leaching and washing are accomplished as before described.

IOO

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'sheet-steel, or iron but is preferably made of light steel. The filtering materials are preferably cocoa-matting and canvas.

For treating slimes the drainage and leaking tank is preferably built circular, high, and narrow, the height exceeding the diameter; but for treating coarser sands or ore it may be built much larger, either square or circular, as preferred,-and may have a plurality of pressure stand-pipes to equalize the pressure in all parts of the tank.

I do not confine myself to the proportions or shape shown in the drawings, but desire to avail myself of such variations in the construction as may be properly made within the true scope of my invention.

I claimias my invention-- 1. In a metallurgie filter, an outer imperforate tank separated by an annular space from an inner drainage and leaching tank with perforated sides and bottom covered with suitable filters, and having within its circumference the perforated lower end of a hollow compartment or stand-pipe through which liquids or compressed air may be introduced into said tank and forced by pressure to pass outwardly through the filters and perforations thereof, and having pipes through which the fiow of such liquids or compressed air may be reversed from the said hollow compartment or stand-pipe into the said annular space'and be forced by pressure to pass inwardly'through the perforations and filters of said tank, substantially as set forth.

2. In a metallurgie filter, an outer imperforate tank and a drainage and leaching tank having perforated sides and bottom, and hav\ ing within its perforated sides a secondary perforated hollow compartment, or standpipe, through which liquids may be introduced into such tankand forced by pressure to permeate and pass through the contents thereof into said outer tank, substantially as set forth.

3. In a metallurgie filter, an outer imperforate tank and a leaching-tank having perforated sides and bottom covered with suitable filter, and having within its circumference the perforated lower end of a stand-pipe, or pressure-column, into which solvent solutions, wash-water, or other liquids may be introduced and then forced to pass outwardly and downwardly through the contents of such tank and out through the filters and perforations thereof by means of the pressure of such liquid column, substantially as set forth.

4:. A drainage or leachage tank having perforated sides and bottom, built within an outer auxiliary tank or solid shell, and having within its circumference a hollow perforated column or stand-pipe, in combination with valved pipes; the arrangement being such that the liquid contained in said stand-pipe and the pressure exerted thereby, may be cutoff from that part of the stand-pipe within said tank, and compressed air introduced therein and forced through the perforations thereof into and through the contents of Ysaid tank for the purpose of compressing them and driving their liquid contents outwardly and downwardly through the perforated sides and bottom of said drainage-tank, substantially as set forth.

JEAN F. WEBB.

In presence of- J EAN F. WEBB, Jr., JAcoB M. MURPHEY. 

